<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <button class="btn1">张学友</button>  <button class="btn2">刘德华</button><br>
     <img src="https://img2.baidu.com/it/u=3430704085,2575873020&fm=253&fmt=auto&app=120&f=JPEG?w=200&h=200" alt="">
    <script>
   let btn1= document.querySelector(".btn1")
     let btn2= document.querySelector(".btn2")
     let img= document.querySelector("img")
    btn1.onclick=()=>{
       img.src="https://img2.baidu.com/it/u=3430704085,2575873020&fm=253&fmt=auto&app=120&f=JPEG?w=200&h=200"
       img.title="张学友"
    }
     btn2.onclick=()=>{
       img.src="https://img1.baidu.com/it/u=1258459675,2314858625&fm=253&fmt=auto&app=138&f=JPEG?w=190&h=190"
       img.title="刘德华"
 
    }
    </script>
</body>
</html>